Steam-engine



(NO Model.) 2 Sheets-Sheet 1.

R. D. WERDEN.

STEAM ENGINE.

No. 500,749. Patented July4, 1893.

NITED STATES PATENT FFICE.

RODOLPIIUS DAVIS \VERDEN, OF CINCINNATI, OHIO.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 500,749, dated July 4,1893.

Application filed December 9, 1892. Se1ial No. 454,673. (No model.)

T0 wZZ whom i mcoy concern:

Be it known that I, RODOLPHUS DAVIS VVERDEN, a subject of the Queen ofGreat Britain, residing at Cincinnati,in the county of Hamilton andState of Ohio, have invented certain new and useful Improvements inSteam-Engines, of which the following is a full, clear, and exactdescription, reference being had to the accompanyng drawings, formingpart of this specification.

My invention relates to all classes of stationary engines but is moreparticularly designed for those engines requiring a uniformity of speedunder varying loads, and it has for its object the improved performanceof suoh eugines whereby there are secured an economy of steam,uniformity of speed under variable loads, the prevention of undue valveleakage, the prevention of terminal pressures below any back pressure,and the prevention of undue cylinder condensation.

The novelty of my invention will be hereinafter set forth andspecifically pointed out in the claims.

In the accompanying drawingsz-Figure 1, Sheet 1, is a sectional planview of an engine embodying my invention. Fig. 2, Sheet 2, is anelevation of the governor, fly, and belt wheels taken on the dotted line00 x of Fig. 1. Fig. 3, Sheet 2, is a plan view of Fig. 2 looking at thesarne in the direction of the arrow at the right, and with portionsbroken away to show the shifting meohanisrn for the valve controllingthe admission of steam to the cylinder.

The sanue letters of referenceare used to indicate identical parts inall the figures.

The construction of the engine, exoept in the particulars to be pointedout, may be that usually employed or it may be of any desiredconstruction,and it is only necessary in describing it to say that, A isthe cylinder, B the steam chest, with the usual ports and with slidevalve (1 and cut off slide b, 0 the piston in the cylinder,l) its rod, Ethe pitman, F the crank or crank disk, G the driving shaft, and

H I the ecoentric rode for the slide valve and cut oi, respectively. Thefly wheel J is fast on the shaft G and has secured upon it in the usualor any suitable manner the yielding driving wheel K with interposedhearing rolleis 0 and connecting springs d,Fig. 2. Loose on the shaft Gbeside the wheel J is the usual or any suitable governor wheel L withWeight e, pivoted weighted arm f and spring g. A lever h Fig. 2,adjustably pivoted as at 1 to the fly wheel arm has its inner endpivoted to the governor wheel as atj and its enter end pivotallyconnected, in this instance by a pivoted link 7 to the wheel K. Likewiseloose upon the shaft G by the side of the governor wheel is theecoentric M for the cut off 1od I While the eccentric N for the slidevalve rod H is fast on the shaft G. The eccentric M has a hub with aprojecting lug Zwhich is adjustably and pivotally connected by a link mto the outer end of the weight armf.

Feathered upon the shaft G is a collar O, Figs. 1 ahd 3 having acircumferential groove in which is confined the fork of a lever Ppivoted as at 11 and suitably connected at its rear to the adjustablestem of the steam controlling valve Q, in this nstance represented as anordinary puppet valve, for admitting steam. to the steam chest. Suitablyjournaled in the fly wheel, in this instance on its hub and through itsri1n, is a radial rod p having its outer end bent to form a crank qengaged loy pins 0 on the inner side of the wheel K, see Figs. 2 and 3,and having its inner end bent to form a crank s which is pivotallyconnected by a link t to the collar 0.

The adjustment of the parts is such that when steam is shut off and theengine at rest the springs d exerting their force on the rod p throw thecollar outward so as to nearly but not entirely close the valve q. Theeccentrics M N are propcrly adj usted to each other, and the weight 6 isdrawn in. The wheel K is beltecl to the load and we will suppose theengine to be started by the admission of steam through the slightly openvalve Q. The first eiect wouldbe the compression of the springs a thewheel K standing still for an instant, and the drawing in of the collar0 thereby opening valve Q to an extent proportionate to the load. At thesame time, and by the same relative movements of the wheels J and K thegovernor wheel is turned forward by lever h thereby shifting, throughmedium of link m, the eccentric M to such a positon that the cut off bdoes not interfere with the full action of the slide valve. As the wheelK begins to turn and the inertia of the load is overeome the whee1 K isshifted forward by the aetion of the spring d thereby e1osing down theva1ve Q t0 admit less steam and bring the eceentric M into sueh positionchat the cut off comes into play t0 eut off at any desired portion ofthe stroke S0 that the steam acts on the piston by its expansion alonebui: nevel to such a degree that it gets below beek pressure at thetermination of the stroke. Should the speed inerease beyond the norma1degree desired the aotion of the weight e wil1 s0 further shift theeecentrie as to cause the eut 0fl" l0 act quicker and thereby preventthe acceleration of the speed. The moment however an extra load eomesen, the wheei K again shifts relativeiy t0 J by being retarded and thevalve Q and eceentrie M are again acted en toedmit proportionatepressure, which is again gradually cut off as the conditions andadjustments again become normal, and to cause the cut off t0 act;quieker. In ths way and by the use of these eompound governors theaetion of the engine is entirely automatic in controlling the properminimum amount of steam and the speed, no matter how the 1oad may bevaried. In this way a1so the eut 0 is made to aet in opposition t0 itsformer plan of use, for With my eonstrnetion the greater the load thequicker the enta off is made.

By way of illustration of the action of the cut off with variable loadsI have shown an indicator diagram in Fig. 1, where it is assnmed thatthe initial pressure at the beginning of the stroke is sixtypounds, andthe 0111 0ff is made at quanter stroke. Under these conditions thepressure at quarter stroke when euta 0ff is made, would be sixty pounds;at half stroke it would be thirty pounds; atthree quarters stroke itwould be twenty-two and ene-half p'ounds, and at the termination of thestroke fifteen pounds or atmospherie pressure, or very slightly abovethis. N0w supposing the load to be decreased S0 as to close vave Q toadmit thirty pounds the eeeentric M would then be adjusted by lever h110 cut off at haif stroke and pressure there would still be thirtypounds, and at three qnarter srroke t would be twenty-tvvo and ene-halfpounds, and at the end of the stroke fifteen ponnds, er slightly aboveas before.

IVhi1e the greatest benefit of my in vention comes from eontrolling thecut off both by the load and the speed, in conn ection with ZL thrott1ing governor, yet a large part of the benefio of my invention e0u1dbe obtained by disconnecting the wheel K from the eceentrc M, throughthe medium of the governor wheel L,

end making the 1atter fast to the shaft G 0r vvheel J. In sueh case theeeeentric M wonld only be adj usted by the speed, as Will be readilyunderstood and while I have shown suitable meehansms fox connecting theload vvhee1 and shaft wheel with the thr ottling gevernor and with thegovernor wheel and eeeentrio for the cnt ofi I do not wish my inventionto be limited to these construetions as they might be varied in avarieiay of ways.

IIaving thus fully descrbed my invention, I claim 1. In en engine, thecombination with a1oad governor mechanism and throttle valve actuatedthereby, of a variable cut off controlled by the speed.

2. In en engine, a variable cut off, a speed governor mechanism, a10adwheel and shafb whee1 with interposed throttle valve mechanism aetuatedby their relative shifting, a connection between the 10ad whee1 andvariable ent off, and a een neeton between the speed governor and.variable cut off, vvhereby the engine is eensed to run with uniformspeed under varying loads substantially as deseribed.

3. In en engine, a variable cut off, a speed governor mechanism, a loadwheel and shaft whee1 with interposed throttle valve mechanism aetuatedby their relative shifting, an eecentrie for said ent 0ff loose on theshaft, a conneetion between the 10ad wheel and eccentric, and aconnection between the speed governor and eceentrie, substantially asdescrbed.

4:. In en engine,the eombination of a s1ide valve, a eut 0ff valve, athrottling valve for the steam chest, a load whee1 and shaft wheel Withinterposed meehanism for aetuating the throttling valve eontrolled bytheir relative shifting, a speed governor an eccentrie 100se on theshaft for the cut; off va1ve, a connection between the leed wheel andsnid eccentrio, and a eonnection between the speed gevernor and saideeeentric, substantiailyas deserbed.

R. DAVIS WERDEN. Witnesses:

J. THOIVISON CROSS, BERNARD J. HAUSF'ELD.

IOO

